The objective of this program is to realize a significant advance in health care delivery for ophthalmic disorders by comprehensive improvements in the capabilities of ultrasonic diagnostic systems. These improvements will enable the reliable detection and identification of a broad class of disorders, so that appropriate treatment can be promptly initiated. Special efforts are directed toward tumor diagnosis in the eye and orbit and assessment of vascular disorders. Experimental and theoretical investigations are aimed at delineating how characteristic tissue structure can be identified by "signatures" involving several sets of ultrasonic parameters. This information is used to design and implement electronic techniques specifically intended to provide characteristic structural information for tissue identification. Clinical evaluations are carried out to develop and refine these techniques in terms of specific diagnostic problems in ophthalmology. The research program is a collaborative effort with clinical studies performed at the Institute of Ophthalmology, Columbia Presbyterian Medical Center, and engineering development performed at Riverside Research Institute.